# AD 68-12-03: High Compressor Rotor Blade Failure

- Type: Airworthiness directive
- Status: Current
- Products: Pratt & Whitney Division JT4A-10, JT4A-11, JT4A-12, JT4A-3, JT4A-5 and JT4A-9
- Effective: June 12, 1968
- Superseded by: Nothing supersedes this AD
- Product type: Engine
- Amendment: 39-608
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/67EA669F0DF3606A8625685B006165F0.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/68-12-03

## The airworthiness directive

68-12-03 PRATT & WHITNEY: Amendment 39-608. Applies to all Model JT4A Series Turbojet Engines. Compliance required as indicated unless previously accomplished.: To preclude penetration of the diffuser case in the event of a high compressor rotor blade failure, accomplish the following: Within the next 11,000 hours' time in service after the effective date of this AD, rework all P/N's 361176, 397231, 419006, 406242, 429614, 447328, and 450862 diffuser case assemblies in accordance with Pratt & Whitney Aircraft Turbojet Engine Service Bulletin No. 1033 dated September 8, 1965, and FAA-approved revisions or an equivalent modification approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. This amendment becomes effective June 12, 1968.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS E-291](https://openairdocs.org/tcds/E-291): Pratt & Whitney Division; names 6 of 6 models: JT4A-11, JT4A-3, JT4A-9, JT4A-10, JT4A-5, JT4A-12

## Registered aircraft it may apply to (OpenAirDocs)

No registered aircraft matched the models it names.

Its text cites no advisory circulars or STCs.

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